Doxycycline for soft tissue gunshot wound infection?

Outside of foot, .22 caliber point blank through leather boot, xrayed and no fragments or bullet, bottom of foot looks great, but top has pus filled blister, and oozing brownish- reddish liquid, can doxycycline clear it up, i have 100mg capsules and i have 90 pills or 180 pills, if so how much dk i take, 1 a day or 2 OR WHAT???